src/cx/allocator.h

Sun, 30 Jan 2022 14:19:00 +0100

author
Mike Becker <universe@uap-core.de>
date
Sun, 30 Jan 2022 14:19:00 +0100
changeset 500
eb9e7bd40a8e
parent 484
9e6900b1cf9d
child 503
a89857072ace
permissions
-rw-r--r--

do not hide pointers behind typedefs

universe@391 1 /*
universe@391 2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
universe@391 3 *
universe@391 4 * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
universe@391 5 *
universe@391 6 * Redistribution and use in source and binary forms, with or without
universe@391 7 * modification, are permitted provided that the following conditions are met:
universe@391 8 *
universe@391 9 * 1. Redistributions of source code must retain the above copyright
universe@391 10 * notice, this list of conditions and the following disclaimer.
universe@391 11 *
universe@391 12 * 2. Redistributions in binary form must reproduce the above copyright
universe@391 13 * notice, this list of conditions and the following disclaimer in the
universe@391 14 * documentation and/or other materials provided with the distribution.
universe@391 15 *
universe@391 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
universe@391 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
universe@391 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
universe@391 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
universe@391 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
universe@391 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
universe@391 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
universe@391 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
universe@391 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
universe@391 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
universe@391 26 * POSSIBILITY OF SUCH DAMAGE.
universe@391 27 */
universe@429 28 /**
universe@429 29 * \file allocator.h
universe@429 30 * Interface for custom allocators.
universe@429 31 */
universe@391 32
universe@391 33 #ifndef UCX_ALLOCATOR_H
universe@391 34 #define UCX_ALLOCATOR_H
universe@391 35
universe@484 36 #include "common.h"
universe@391 37
universe@415 38 #ifdef __cplusplus
universe@415 39 extern "C" {
universe@415 40 #endif
universe@415 41
universe@429 42 /**
universe@429 43 * The class definition for an allocator.
universe@429 44 */
universe@396 45 typedef struct {
universe@429 46 /**
universe@465 47 * The allocator's malloc() implementation.
universe@429 48 */
universe@405 49 void *(*malloc)(void *data, size_t n);
universe@429 50
universe@429 51 /**
universe@465 52 * The allocator's realloc() implementation.
universe@429 53 */
universe@450 54 void *(*realloc)(void *data, void *mem, size_t n)
universe@450 55 __attribute__((__warn_unused_result__));
universe@429 56
universe@429 57 /**
universe@465 58 * The allocator's calloc() implementation.
universe@429 59 */
universe@405 60 void *(*calloc)(void *data, size_t nelem, size_t n);
universe@429 61
universe@429 62 /**
universe@465 63 * The allocator's free() implementation.
universe@429 64 */
universe@450 65 void (*free)(void *data, void *mem)
universe@450 66 __attribute__((__nonnull__));
universe@396 67 } cx_allocator_class;
universe@396 68
universe@429 69 /**
universe@429 70 * Structure holding the data for an allocator.
universe@429 71 */
universe@394 72 struct cx_allocator_s {
universe@429 73 /**
universe@429 74 * A pointer to the instance of the allocator class.
universe@429 75 */
universe@396 76 cx_allocator_class *cl;
universe@429 77 /**
universe@429 78 * A pointer to the data this allocator uses.
universe@429 79 */
universe@397 80 void *data;
universe@391 81 };
universe@429 82
universe@429 83 /**
universe@429 84 * High-Level type alias for the allocator type.
universe@429 85 */
universe@500 86 typedef struct cx_allocator_s CxAllocator;
universe@391 87
universe@429 88 /**
universe@429 89 * A default allocator using standard library malloc() etc.
universe@429 90 */
universe@500 91 extern CxAllocator *cxDefaultAllocator;
universe@391 92
universe@429 93 /**
universe@429 94 * Allocate \p n bytes of memory.
universe@429 95 *
universe@429 96 * @param allocator the allocator
universe@429 97 * @param n the number of bytes
universe@429 98 * @return a pointer to the allocated memory
universe@429 99 */
universe@500 100 void *cxMalloc(
universe@500 101 CxAllocator *allocator,
universe@500 102 size_t n
universe@500 103 )
universe@461 104 __attribute__((__malloc__))
universe@461 105 __attribute__((__alloc_size__(2)));
universe@397 106
universe@429 107 /**
universe@429 108 * Re-allocate the previously allocated block in \p mem, making the new block \p n bytes long.
universe@429 109 * This function may return the same pointer that was passed to it, if moving the memory
universe@429 110 * was not necessary.
universe@429 111 *
universe@429 112 * \note Re-allocating a block allocated by a different allocator is undefined.
universe@429 113 *
universe@429 114 * @param allocator the allocator
universe@429 115 * @param mem pointer to the previously allocated block
universe@429 116 * @param n the new size in bytes
universe@429 117 * @return a pointer to the re-allocated memory
universe@429 118 */
universe@500 119 void *cxRealloc(
universe@500 120 CxAllocator *allocator,
universe@500 121 void *mem,
universe@500 122 size_t n
universe@500 123 )
universe@461 124 __attribute__((__warn_unused_result__))
universe@461 125 __attribute__((__alloc_size__(3)));
universe@397 126
universe@429 127 /**
universe@429 128 * Re-allocate a previously allocated block and changes the pointer in-place, if necessary.
universe@429 129 * This function acts like cxRealloc() using the pointer pointed to by \p mem.
universe@429 130 * On success, the pointer is changed to the new location (in case the
universe@429 131 *
universe@429 132 * \note Re-allocating a block allocated by a different allocator is undefined.
universe@429 133 *
universe@429 134 * \par Error handling
universe@429 135 * \c errno will be set, if the underlying realloc function does so.
universe@429 136 *
universe@429 137 * @param allocator the allocator
universe@429 138 * @param mem pointer to the pointer to allocated block
universe@429 139 * @param n the new size in bytes
universe@429 140 * @return zero on success, non-zero on failure
universe@429 141 */
universe@500 142 int cxReallocate(
universe@500 143 CxAllocator *allocator,
universe@500 144 void **mem,
universe@500 145 size_t n
universe@500 146 )
universe@452 147 __attribute__((__nonnull__));
universe@414 148
universe@429 149 /**
universe@429 150 * Allocate \p nelem elements of \p n bytes each, all initialized to zero.
universe@429 151 *
universe@429 152 * @param allocator the allocator
universe@429 153 * @param nelem the number of elements
universe@429 154 * @param n the size of each element in bytes
universe@429 155 * @return a pointer to the allocated memory
universe@429 156 */
universe@500 157 void *cxCalloc(
universe@500 158 CxAllocator *allocator,
universe@500 159 size_t nelem,
universe@500 160 size_t n
universe@500 161 )
universe@461 162 __attribute__((__malloc__))
universe@461 163 __attribute__((__alloc_size__(2, 3)));
universe@397 164
universe@429 165 /**
universe@429 166 * Free a block allocated by this allocator.
universe@429 167 *
universe@429 168 * \note Freeing a block of a different allocator is undefined.
universe@429 169 *
universe@429 170 * @param allocator the allocator
universe@429 171 * @param mem a pointer to the block to free
universe@429 172 */
universe@500 173 void cxFree(
universe@500 174 CxAllocator *allocator,
universe@500 175 void *mem
universe@500 176 )
universe@452 177 __attribute__((__nonnull__));
universe@391 178
universe@415 179 #ifdef __cplusplus
universe@415 180 } /* extern "C" */
universe@415 181 #endif
universe@415 182
universe@393 183 #endif /* UCX_ALLOCATOR_H */

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